After several rumors and leaks, Samsung officially presented in late February a most member of your Galaxy M familyspecifically, the successor to the Galaxy M30 and Galaxy M30s. This new model, called Galaxy M31, landed on the market just two months later, in early May, with a price that placed it directly in the manufacturer’s mid-range.

In addition to betting on a huge 6,000 mAh battery Like its predecessor, the new Samsung device arrives with the focus on photography and, therefore, it has raised both the number of sensors and the maximum resolution of its rear camera. At Xataka Móvil, we have already had the opportunity to test it thoroughly and below we will tell you how the Galaxy M31 behaves in each section.

Data sheet of the Samsung Galaxy M31



6.4 inch Super AMOLED
FullHD + resolution

Gorilla Glass 3


Exynos 9611


6 GB


64GB + MicroSD up to 512GB

Frontal camera

32 MP f / 2.0

Rear camera

64 MP f / 1.8
8 MP wide angle f / 2.2
5 MP depth f / 2.2
5 MP macro f / 2.4


6,000 mAh
Fast charge 15W

Operating system

Android 10 + One UI 2.0


4G, Dual SIM, Wi-Fi 5, Bluetooth 5, NFC, USB-C, 3.5mm jack


Rear fingerprint reader

Dimensions and weight

159.2 x 75.1 x 8.9 mm
191 g


279 euros

Samsung Galaxy M31 – Dual SIM Smartphone, 6.4 “sAMOLED FHD + Screen, 64 MP Camera, 6 GB RAM, Expandable 64 GB ROM, 6000 mAh Battery, Android, Spanish Version, Black Color

A display that shines in a sober design

Samsung Galaxy M31 RearSamsung Galaxy M31 Rear

The first thing that jumps out at the Galaxy M31 is a continuous design, which go back to the plastic for the back and that it does not present great differences with respect to the previous model. Although it is also available in black or red, the unit that has passed through our hands is the bright blue color, a uniform dark blue (without gradient) that you will rarely see clean because the presence of traces and dirt is inevitable.

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That back has slightly curved sides, which, added to its rounded corners, makes it comfortable and pleasant in the hand. It is true that its thickness of 8.9 mm and its weight of 191 g prevent us from talking about a light and thin terminal, but they are not figures at all exaggerated considering the enormous battery that it carries on board. Both the camera module and the fingerprint reader protrude very little from the body, so it hardly limps when we place it face up on a smooth surface.

Samsung Galaxy M31 Camera 02Samsung Galaxy M31 Camera 02

On the front, we have a 6.4-inch Super AMOLED panel with FullHD + resolution and a discreet drop-shaped notch where the front camera is housed. Although the lower edge is somewhat thick, the use of the front is quite good for a model of this category. That screen we have been pleasantly surprised when it comes to the viewing experience, with correct colors, optimal viewing angles and maximum brightness, which has allowed us to use the terminal perfectly even in direct sunlight.

Samsung Galaxy M31 DesignSamsung Galaxy M31 Design

The tactile response and automatic brightness have also given us good results. And the oleophobic treatment here is indeed efficient. In addition, we can not ignore the customization options that One UI offers us, among which we find, for example, the possibility of increasing touch sensitivity to use it with a screen protector and manual adjustment of the white balance in case we prefer it cooler or warmer.

Samsung Galaxy M31 PortsSamsung Galaxy M31 Ports

At the bottom of the Galaxy M31, we have a single speaker next to the USB-C port and headphone jack. That speaker offers a fairly fair sound, with improvable power and quality, especially when increasing the volume. We have not been able to verify the behavior of the headphones because they are not included as standard; negative point for samsung in this regard.

The great asset is autonomy

Samsung Galaxy M31 PerformanceSamsung Galaxy M31 Performance

Under the chassis of the Galaxy M31, we find the Exynos 9611, a brand-name octa-core processor that we already saw in its predecessor, the Galaxy M30s. Where there is a step forward is in the RAM, which is now 6 GB. The whole of it provides a good user experience even in multitasking, with good transitions and no delay when going from one app to another.

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Performance for everyday tasks is therefore more than enough, but what happens when we put it to the test with demanding games? There he experiences some difficulties, which are not exaggerated, but which could have been avoided by opting for a more powerful processor. In addition, we have noticed that the phone gets a little warm when we demand too much, although we cannot say that this temperature rise is excessive. Next, we leave you the results of the most common benchmarks:







Exynos 9611

Exynos 9611

Exynos 9611

Kirin 810

Snapdragon 720G


6 GB



6 GB









347 / 1,280

347 / 1,338

546 / 1,607







Samsung Galaxy M31 BenchmarksSamsung Galaxy M31 Benchmarks

The Galaxy M31 has two biometric authentication systems: the rear fingerprint sensor and facial recognition. The latter is a little slow, but very effective and identify our face even in the dark. In addition, it invites us to register our face with and without glasses to recognize it when we wear them. The fingerprint sensor also works well, as long as we can put our finger on it, something that is a bit difficult due to its size and because it protrudes so little that it is difficult to locate it by touch.

The fingerprint sensor works well, as long as we can put our finger on it, which is a bit difficult

In the software section, we have the latest from Google (Android 10) with the latest from Samsung (One UI 2.0). It is a polished and colorful layer that offers us intuitive navigation, numerous customization options and various tools that can be useful to us. Although the amount of bloatware has decreased in recent years, Samsung continues to introduce several proprietary apps – some duplicates – and third-party apps, which in this case are Netflix, Spotify, Facebook and the Microsoft package.

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Initially, about 48 GB of the 64 GB of capacity come free; The good thing is that some of those apps can be uninstalled without problems and that we can always resort to a microSD card of up to 512 GB to increase storage, without giving up its Dual SIM function, since it has a triple card tray.

Let’s go now with the highlight of this Samsung: its autonomy. As we said at the beginning, the great asset of this model is that it has a 6,000 mAh battery that it lasts two days with medium use. Even if we demand a lot from him, he will reach the end of the day with autonomy to spare. In our tests, it has given us around 10 hours of screen, depending on whether we were abusing the camera and the games.

Samsung Galaxy M31 BatterySamsung Galaxy M31 Battery

Its 15 W fast charging system, however, is not as fast as we would like -validity redundancy-: plugged into the power with the charger that comes standard, has taken time about 3 hours to get a full charge, and in 30 minutes, it has barely achieved 22-25% energy. Although of course, a 25% charge on this phone goes a long way.

The photographic equipment, another pleasant surprise

Samsung Galaxy M31 CameraSamsung Galaxy M31 Camera

Our next stop is the photographic equipment, which in the Galaxy M31 comes materialized in a 32-megapixel front camera with f / 2.0 aperture and a rear camera with four sensors– The main 64-megapixel f / 1.8, 8-megapixel wide-angle with a 123 ° angle of view, and two other 5-megapixel sensors each for depth readings and macro photography respectively. And something to be thankful for: 4K video recording at 30 fps.

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The camera application is the usual one that Samsung is used to, intuitive, simple and with shortcuts to the main functions and shooting modes. Initially, we have three: Dynamic Focus (they could have called it Portrait, the truth), Photo (automatic) and Video, but in the More tab, in addition to Bixby Vision and AR Emoji, we find more shooting modes we can add to the lower carousel (Macro, Night, Pro, Panoramic, Food, Fast Motion, Slow Motion and Super Slow Motion).

Yes we miss a shortcut to enable and disable HDR, which is hidden in Settings, and another to apply its numerous beauty effects, which appear next to the filters when you click on the magic wand. Reaching them is so little intuitive, that we end up not using them and always keeping HDR activated.

Samsung Galaxy M31 DiaSamsung Galaxy M31 Dia Photo mode (automatic)

Now let’s talk about the quality that this rear camera offers us. Photo or auto mode uses Pixel Binning technology to group 4 pixels into 1 for brighter 16 MP photos. The day results are very satisfactory, with good dynamic range and high level of detail, even in scenes with light contrasts. Scene recognition is very accurate and AF behaves quickly and effectively.

Samsung Galaxy M31 Angular DaySamsung Galaxy M31 Dia Angular “Normal” Photo Mode (1X) vs. Wide angle photo mode (0.5X)

When using the wide angle (which also has a shortcut), some detail is lost and the edges of the image are deformed, but the color treatment is still good. Two modes that we especially liked are the Macro mode (which allows shooting at short distances with a background blur that highlights the foreground) and the Dynamic Focus mode (which gives us the possibility to adjust the bokeh effect to our liking).

Samsung Galaxy M31 Day PortraitSamsung Galaxy M31 Dia Portrait Photo mode (left) vs. Dynamic Focus mode with blurring to the maximum (right)

By maximizing background blur in that Dynamic Focus mode for portraits, the cut may end up being somewhat artificial, but if we adjust it in the midpoints, the result is very positive.

In our tests, we have seen that Night mode, far from contributing anything, reduces the angle of view and slows down image processing

At night, the image quality is reduced and noise appears, as expected, but the Galaxy M31 manages to save the scenes with dignity. It is true that it blurs faraway points of light, but the AF is still fast and the level of detail is higher than in other models in its category. Curiously, in our tests, we have appreciated that the Night mode does not contribute much on this phone. What’s more, it reduces the viewing angle and slows down image processing.

Samsung Galaxy M31 Night 2Samsung Galaxy M31 Night 2 Photo mode (left) vs. Night mode (right)

We now turn to the front camera of the Samsung Galaxy M31. By day, Photo mode gets very good results in terms of detail, color and sharpness, although in the background a lot of noise does appear. Dynamic Focus mode here uses software to achieve adjustable background blur at different levels; to the maximum, it generates an artificial cut and shows difficulties in identifying the limits of the hair or sunglasses.

Samsung Galaxy M31 Selfie Dia 2Samsung Galaxy M31 Selfie Dia 2 Front Camera Photo Mode

Samsung Galaxy M31 Selfie PortraitSamsung Galaxy M31 Selfie Portrait Photo mode (left) vs. Dynamic Focus mode with background blurring at maximum (right)

And at night? As usually happens in models in this category, the quality of the photos decreases considerably, with an obvious presence of noise and loss of sharpness; In addition, the white balance usually “yellows” the faces, unless we use the on-screen flash (not recommended), in which case our faces will appear whitish.

Samsung Galaxy M31 Selfie NightSamsung Galaxy M31 Selfie Night Front Camera Photo Mode

Even with everything, the nightly selfies that the Galaxy M31 gives us they are much more acceptable than those offered by other terminals from your price range. Night mode, by the way, is also available on the front camera, but it has not convinced us: it takes so long to capture the photo, that any movement causes our face and the background to be out of focus.

Samsung Galaxy M31, the opinion of Xataka Móvil

Samsung Galaxy M31 CoverSamsung Galaxy M31 Cover

After several days of use, the Samsung Galaxy M31 has left a good taste in our mouth: it is a mid-range terminal that could well be included in the Galaxy A line from the South Korean manufacturer, in theory, somewhat above the M. If we look at each section one by one, the Galaxy M31 stands out especially for its screen (typical of the upper-middle range) and its autonomy (which allows us to forget about the charger during almost two days).

If we look at each section one by one, the Galaxy M31 stands out especially for its screen and autonomy, although its cameras also surprise for good

It is true that the performance is fair, that the sound is not strong and that the loading speed is slower than we would like, but in return, this model puts at our disposal some cameras that will satisfy us in most cases. As for the design, without being a display of elegance and with the fingerprints “tattooed” on the back, it must be recognized that Samsung has achieved a good finish.

In short, whenever you like Samsung’s One UI layer, we are dealing with a recommended model, whose only problem is the price -279 euros-, especially, considering that it comes without headphones, without a case and without a screen protector. And judging by the scratches that the terminal shows, these last two accessories are essential. It is true that it will drop in price soon and it will be possible to buy much cheaper, but right now, for 279 euros, there are competing models one step ahead in terms of benefits.








In favor

Its autonomy will not leave you lying. A screen typical of superior models. General behavior of the cameras.


The Exynos 9611 suffers with demanding games despite 6 GB of RAM. It takes almost 3 hours to fully charge. A single speaker that offers somewhat poor sound.

Samsung Galaxy M31 - Dual SIM Smartphone, 6.4 Screen

Samsung Galaxy M31 – Dual SIM Smartphone, 6.4 “sAMOLED FHD + Screen, 64 MP Camera, 6 GB RAM, Expandable 64 GB ROM, 6000 mAh Battery, Android, Spanish Version, Black Color